Method for Transmitting or Receiving a Mac Pdu in a Wireless Communication System and a Device Therefor

1. A method for a device operating in a wireless communication system, the method comprising: generating a MAC protocol data unit (PDU) including a MAC PDU subheader, the MAC PDU subheader including a first octet of 8 bits followed by a second octet of 8 bits, wherein the first octet includes a logical channel identity (LCID) field consisting of 5 bits; and transmitting the generated MAC PDU to a second device in the wireless communication system, wherein, based on the 5 bits of the LCID field being set to a specific value, the LCID field indicates that the second octet includes an extended LCID (eLCID) field comprising more than 5 bits that identify either a corresponding logical channel of a MAC service data unit (SDU) or a corresponding type of a MAC control element (CE), otherwise, the eLCID is not included in the MAC PDU subheader and the 5 bits of the LCID field identify either a corresponding logical channel of a MAC SDU or a corresponding type of a MAC CE, and wherein the generated MAC PDU further includes either a MAC SDU or a MAC CE corresponding to a respective one of the LCID or eLCID.

2. The method of claim 1 , wherein the MAC PDU subheader further includes a length field indicating a length of the MAC SDU or the MAC CE, and wherein the eLCID field is followed by the length field in the MAC PDU subheader.

3. The method of claim 1 , wherein the device is a base station (BS) and the second device is a user equipment (UE).

4. The method of claim 1 , wherein the device is a user equipment (UE) and the second device is a base station (BS).

5. The method of claim 1 , wherein the device is configured by the second device to generate the MAC PDU.

6. A device operating in a wireless communication system, the device comprising: a memory; a transceiver; and a processor operatively connected to the memory and the transceiver, the processor configured for: generating a MAC protocol data unit (PDU) including a MAC PDU subheader, the MAC PDU subheader including a first octet of 8 bits followed by a second octet of 8 bits, wherein the first octet includes a logical channel identity (LCID) field consisting of 5 bits; and transmitting the generated MAC PDU to a second device in the wireless communication system, wherein, based on the 5 bits of the LCID field being set to a specific value, the LCID field indicates that the second octet includes an extended LCID (eLCID) field comprising more than 5 bits that identify either a corresponding logical channel of a MAC service data unit (SDU) or a corresponding type of a MAC control element (CE), otherwise, the eLCID is not included in the MAC PDU subheader and the 5 bits of the LCID field identify either a corresponding logical channel of a MAC SDU or a corresponding type of a MAC CE, and wherein the generated MAC PDU further includes either a MAC SDU or a MAC CE corresponding to a respective one of the LCID or eLCID.

7. The device of claim 6 , wherein the MAC PDU subheader further includes a length field indicating a length of the MAC SDU or the MAC CE, and wherein the eLCID field is followed by the length field in the MAC subheader.

8. The device of claim 6 , wherein the device is a base station (BS) and the second device is a user equipment (UE).

9. The device of claim 6 , wherein the device is a user equipment (UE) and the second device is a base station (BS).

10. The device of claim 6 , wherein the device is configured by the second device to generate the MAC PDU.

11. A method for a device operating in a wireless communication system, the method comprising: receiving, from a second device in the wireless communication system, a MAC protocol data unit (PDU) including a MAC PDU subheader, the MAC PDU subheader including a first octet of 8 bits followed by a second octet of 8 bits, wherein the first octet includes a logical channel identity (LCID) field consisting of 5 bits; and decoding the MAC PDU, wherein, based on the 5 bits of the LCID field being set to a specific value, the LCID field indicates that the second octet includes an extended LCID (eLCID) field comprising more than 5 bits that identify either a corresponding logical channel of a MAC service data unit (SDU) or a corresponding type of a MAC control element (CE), otherwise, the eLCID is not included in the MAC PDU subheader and the 5 bits of the LCID field identify either a corresponding logical channel of a MAC SDU or a corresponding type of a MAC CE, and wherein the MAC PDU further includes either a MAC SDU or a MAC CE corresponding to a respective one of the LCID or eLCID.

12. The method of claim 11 , wherein the MAC PDU subheader further includes a length field indicating a length of the MAC SDU or the MAC CE, and wherein the eLCID field is followed by the length field in the MAC subheader.

13. The method of claim 11 , wherein the device is a base station (BS) and the second device is a user equipment (UE).

14. The method of claim 11 , wherein the device is a user equipment (UE) and the second device is a base station (BS).

15. A device operating in a wireless communication system, the device comprising: a memory; a transceiver; and a processor operatively connected to the memory and the transceiver, the processor configured for: receiving, from a second device in the wireless communication system, a MAC protocol data unit (PDU) including a MAC PDU subheader, the MAC PDU subheader including a first octet of 8 bits followed by a second octet of 8 bits, wherein the first octet includes a logical channel identity (LCID) field consisting of 5 bits; and decoding the MAC PDU, wherein, based on the 5 bits of the LCID field being set to a specific value, the LCID field indicates that the second octet includes an extended LCID (eLCID) field comprising more than 5 bits that identify either a corresponding logical channel of a MAC service data unit (SDU) or a corresponding type of a MAC control element (CE), otherwise, the eLCID is not included in the MAC PDU subheader and the 5 bits of the LCID field identify either a corresponding logical channel of a MAC SDU or a corresponding type of a MAC CE, and wherein the generated MAC PDU further includes either a MAC SDU or a MAC CE corresponding to a respective one of the LCID or eLCID.

16. The device of claim 15 , wherein the MAC PDU subheader further includes a length field indicating a length of the MAC SDU or the MAC CE, and wherein the eLCID field is followed by the length field in the MAC subheader.

17. The device of claim 15 , wherein the device is a base station (BS) and the second device is a user equipment (UE).

18. The device of claim 15 , wherein the device is a user equipment (UE) and the second device is a base station (BS).

19. The device of claim 15 , wherein the device is configured by the second device to generate the MAC PDU.